Prescription Drugs

CLINICAL PHARMACOLOGY Pentazocine is a potent analgesic which when administered orally is approximately equivalent, on a mg for mg basis, in analgesic effect to codeine. Two caplets of TALWIN Compound (pentazocine and aspirin) when administered orally have the additive analgesic effect equivalent to 25 mg of TALWIN plus 650 mg of aspirin. TALWIN Compound (pentazocine and aspirin) provides the analgesic effects of pentazocine and the analgesic, anti-inflammatory, and antipyretic actions of aspirin. Onset of significant analgesia usually occurs between 15 and 30 minutes after oral administration, and duration of action is usually three hours or longer. Onset and duration of action and the degree of pain relief are related both to dose and the severity of pretreatment pain. Pentazocine weakly antagonizes the analgesic effects of morphine, meperidine, and phenazocine; in addition, it produces incomplete reversal of cardiovascular, respiratory, and behavioral depression induced by morphine and meperidine. Pentazocine has about 1 / 50 the antagonistic activity of nalorphine. It also has sedative activity.

DESCRIPTION TALWIN Compound (pentazocine and aspirin) is a combination of pentazocine hydrochloride, USP, equivalent to 12.5 mg base and aspirin, USP, 325 mg. Pentazocine is a member of the benzazocine series (also known as the benzomorphan series). Chemically, pentazocine is 1, 2, 3, 4, 5, 6 -hexahydro - 6, 11-dimethyl-3-(3-methyl-2-butenyl)-2, 6-methano-3-benzazocin-8-ol, a white, crystalline substance soluble in acidic aqueous solutions. The structual formula is: Chemically, aspirin is Benzoic acid, 2-(acetyloxy)-. Inactive Ingredients: Magnesium Stearate, Microcrystalline Cellulose, Sodium Lauryl Sulfate, Starch.

INDICATIONS For the relief of moderate pain DOSAGE AND ADMINISTRATION Adults. The usual adult dose is 2 caplets three or four times a day. Pediatric Patients. Since clinical experience in pediatric patients under 12 years of age is limited, administration of TALWIN Compound (pentazocine and aspirin) in this age group is not recommended. Duration of Therapy. Patients with chronic pain who receive pentazocine orally for prolonged periods have only rarely been reported to experience withdrawal symptoms when administration was abruptly discontinued (see WARNINGS). Tolerance to the analgesic effect of pentazocine has also been reported only rarely. Significant abnormalities of liver and kidney function tests have not been reported, even after prolonged administration of pentazocine. HOW SUPPLIED Caplets, white, each containing pentazocine hydrochloride equivalent to 12.5 mg base and aspirin 325 mg. Bottles of 100 (NDC 0024-1927-04). Store at room temperature up to 30° C (86° F).

PATIENT INFORMATION No Information Provided.

OVERDOSE Manifestations: Clinical experience with pentazocine overdosage has been insufficient to define the signs of this condition. Signs of salicylate overdosage include headache, dizziness, confusion, tinnitus, diaphoresis, thirst, nausea, vomiting, diarrhea, tachycardia, tachypnea, Kussmaul breathing, convulsions, and coma. Death is usually from respiratory failure. Treatment: Treatment for overdosage of TALWIN Compound (pentazocine and aspirin) , should include treatment for salicylate poisoning as outlined in standard references. Oxygen, intravenous fluids, vasopressors, and other supportive measures should be employed as indicated. Assisted or controlled ventilation should also be considered. For respiratory depression due to overdosage or unusual sensitivity to pentazocine, parenteral naloxone is a specific and effective antagonist. CONTRAINDICATIONS TALWIN Compound (pentazocine and aspirin) should not be administered to patients who are hypersensitive to either pentazocine or salicylates, or in any situation where aspirin is contraindicated.

SIDE EFFECTS Reactions reported after oral administration of pentazocine or TALWIN Compound (pentazocine and aspirin) include Gastrointestinal: nausea, vomiting; infrequently constipation; and rarely abdominal distress, anorexia, diarrhea. CNS Effects: dizziness, lightheadedness, hallucinations, sedation, euphoria, headache, confusion, disorientation; infrequently weakness, disturbed dreams, insomnia, syncope, visual blurring and focusing difficulty, depression; and rarely tremor, irritability, excitement, tinnitus. Autonomic: sweating; infrequently flushing; and rarely chills. Allergic: infrequently rash; and rarely urticaria, edema of the face, and angioneurotic edema. Cardiovascular: infrequently decrease in blood pressure, tachycardia. Hematologic: rarely depression of white blood cells (especially granulocytes), which is usually reversible, moderate transient eosinophilia. Other: rarely respiratory depression, urinary retention, paresthesia, angioneurotic edema, serious skin reactions, including erythema multiforme, Stevens-Johnson syndrome and toxic epidermal necrolysis. DRUG INTERACTIONS No Information Provided.

WARNINGS Drug Dependence. There have been instances of psychological and physical dependence on parenteral pentazocine in patients with a history of drug abuse, and rarely, in patients without such a history. Abrupt discontinuance following the extended use of parenteral pentazocine has resulted in withdrawal symptoms. There have been a few reports of dependence and of withdrawal symptoms with orally administered pentazocine. Patients with a history of drug dependence should be under close supervision while receiving TALWIN Compound (pentazocine and aspirin) orally. There have been rare reports of possible abstinence syndromes in newborns after prolonged use of pentazocine during pregnancy. In prescribing TALWIN Compound (pentazocine and aspirin) for chronic use, the physician should take precautions to avoid increases in dose by the patient and to prevent the use of the drug in anticipation of pain rather than for the relief of pain. Head Injury and Increased Intracranial Pressure. The respiratory depressant effects of pentazocine and its potential for elevating cerebrospinal fluid pressure may be markedly exaggerated in the presence of head injury, other intracranial lesions, or a preexisting increase in intracranial pressure. Furthermore, pentazocine can produce effects which may obscure the clinical course of patients with head injuries. In such patients, TALWIN Compound (pentazocine and aspirin) must be used with extreme caution and only if its use is deemed essential. Usage in Pregnancy. Safe use of pentazocine during pregnancy (other than labor) has not been established. Animal reproduction studies have not demonstrated teratogenic or embryotoxic effects. However, TALWIN Compound (pentazocine and aspirin) should be administered to pregnant patients (other than labor) only when, in the judgment of the physician, the potential benefits outweigh the possible hazards. Patients receiving pentazocine during labor have experienced no adverse effects other than those that occur with commonly used analgesics. TALWIN Compound (pentazocine and aspirin) , should be used with caution in women delivering premature infants. Acute CNS Manifestations. Patients receiving therapeutic doses of pentazocine have experienced hallucinations (usually visual), disorientation, and confusion which have cleared spontaneously within a period of hours. The mechanism of this reaction is not known. Such patients should be closely observed and vital signs checked. If the drug is reinstituted it should be done with caution since these acute CNS manifestations may recur. Due to the potential for increased CNS depressant effects, alcohol should be used with caution in patients who are currently receiving pentazocine. Usage in pediatric patients. Because clinical experience in children under 12 years of age is limited, administration of TALWIN Compound (pentazocine and aspirin) in this age group is not recommended. Ambulatory Patients. Since sedation, dizziness, and occasional euphoria have been noted, ambulatory patients should be warned not to operate machinery, drive cars, or unnecessarily expose themselves to hazards. Other. Because of its aspirin content, TALWIN Compound (pentazocine and aspirin) should be used with caution in the presence of peptic ulcer, in conjunction with anticoagulant therapy, or in any situation where the effects of aspirin may be deleterious. PRECAUTIONS Certain Respiratory Conditions. Although respiratory depression has rarely been reported after oral administration of pentazocine, TALWIN Compound (pentazocine and aspirin) , should be administered with caution to patients with respiratory depression from any cause, severely limited respiratory reserve, severe bronchial asthma and other obstructive respiratory conditions, or cyanosis. Impaired Renal or Hepatic Function. Decreased metabolism of the drug by the liver in extensive liver disease may predispose to accentuation of side effects. Although laboratory tests have not indicated that pentazocine causes or increases renal or hepatic impairment, TALWIN Compound (pentazocine and aspirin) should be administered with caution to patients with such impairment. Myocardial Infarction. As with all drugs, TALWIN Compound (pentazocine and aspirin) should be used with caution in patients with myocardial infarction who have nausea or vomiting. Biliary Surgery. Narcotic drug products are generally considered to elevate biliary tract pressure for varying periods following administration. Some evidence suggests that pentazocine may differ in this respect (i.e., it causes little or no elevation in biliary tract pressures). The clinical significance of these findings, however, is not yet known. Patients Receiving Narcotics. Pentazocine is a mild narcotic antagonist. Some patients previously given narcotics, including methadone for the daily treatment of narcotic dependence, have experienced withdrawal symptoms after receiving pentazocine. CNS Effect. Caution should be used when pentazocine is administered to patients prone to seizures. Seizures have occurred in a few such patients in association with the use of pentazocine although no cause and effect relationship has been established. Pediatric Use. For usage in pediatric patients see WARNINGS .